Film processing machine

ABSTRACT

A film processing apparatus having a row of film developing tanks and a plurality of wires positioned above the tanks. The wires slidingly support a carriage over the row of developing tanks and also function as conductors to switches associated with the carriage. These switches control a motor for stopping the carriage over a successive tank and for reversing the motor to lower the film to be developed into the tank. The starting of the motor is controlled by a tape recorder that plays back tape on which audio-frequency signals of predetermined durations at predetermined intervals have been recorded.

United States Patent Hill [54] FILM PROCESSING MACHINE [72] Inventor:David E. Hill, 611 Perry St., Apt. 2,

Davenport, Iowa 52803 [22] Filed: Aug. 3, 1971 [21] Appl. No.: 168,636

52 US. Cl. ..9s/s9 1) 51 im. CL; ..G03d 3/00 58 Field of Search.;..95/s9 D [56] References Cited I UNITED STATES PATENTS 3,343,4729/1967 Rosenberg ..95/94 R 3,177,767 4/1965 Templeman ..353/15 2,933,0324/1960 Pardee ..95/89 D 3,079,852 3/1963 Little et al. ..95/89 D2,453,900 1 1/1948 Gardiner et al ..95/89 D Y 3,187,626 6/1965 Mindellet al, ..353/l5 [451 Dec. 5, 1972 Primary Examiner-Samuel S/MatthewsAssistant Examiner-Richard M. Sheer Attorney-Jlenderson & Strom [s7]ABSTRACT cy signals of predetermined durations at predeterminedintervals have been recorded.

5 5 Claims, 4 Drawing Figures PATENTEDuEc 5 I972 SHEET 1 BF 2 OZ mm|NVENTOR3 DAVID E. HILL SHEET 2 (IF 2 mmubcommmm mmemoumm mm E.

PATENTED HEB 51972 INVENTOR: DAVID E. HILL ATTORNEY; AWufh 1 FILMPROCESSING MACHINE BACKGROUND OF THE INVENTION This invention pertainsto film .processing machines of the type that have anarrangement oftanks containing film processing solutions and means for automaticallylowering film into the tanks and successively transporting the filmbetween the tanks.

Commercial machines for processing film have containers or tanks .ofprocessing solutions arranged in a row, or in a circle, and have acarriage d'rivingly cou-' pled to an electric motor for transporting thefilm between the tanks and for successively immersing the film inthesolution in thetanks for predetermined intervals. .Various drivingarrangements for transporting the film between the tanks include chainand sprocket wheel arrangements and lead-screw arrangements connectedbetween the motor and a carriage. The carriage may be supported at theend of anarm, and the arm solutions. Other arrangements use a reel and achain or a cord, and the chain or cord'is unreeled to lower-the filminto the solutions.

US. Pat. No. 2,453,900 issued to Nov. 16, I948 shows a pair of parallelrails and a carriage slidingly mounted on the rails. A reel and anelectric motor drivinglycoupled to the reel are mounted at one end ofthe rails, and a cord extends from the reel through a pulley on thecarriage to a film holder. After the carriage is positioned at that endof the rails opposite the motor, the motor is operated at intervals topull the carriage between tanks while the holder is held upwardly closeto the carriage, and after the motor stops operating, the weight of thefilm holder unwinds the reel to lower the film into the tank over whichthe carriage has been positioned. A trip rod is provided for stoppingthe motor when the carriage is over a tank. The carriage slides alongthe rod until a cog on the car-. riage engages a notch in the rod, andthen the rod is moved in the direction of the movement of the carriageto operate a'circuit breaker for stopping the motor.

In different commercial film processing machines, a timer is provided tocontrol the'operation of the motor for determining movement of thecarriage. The timer usually comprises an electric motor and acamoperated switching arrangement.

BRIEF DESCRIPTION OF THE INVENTION An object of this invention is toprovide an automatic film developer that is simple enough and low enoughin cost to encourage its use by hobbyists at home.

A row of tanks for processing solutions and rinse are placed on thebottom of a long, narrow box that has a side cover to exclude-light. Aspace is provided ahead of the processing tanks for location of a filmcontainer having a tight lid. A darkroom is not required because aphotographic changing bag and the container can be used to exclude lightbefore the side cover is placed on the box.

Three wires are suspended .over the row of tanks to function as a trackfor a carriage and also as conductors for a switching system thatcontrols movement of the carriage, A film holder is connected to one endof a cord; the cord is passed through an eye attached to the undersideof the carriage; and then it is extended to a reel that is rotatablymounted in that end of the box W.R. Gardner on that extends past thelast tank into which the film is to be lowered. The reel is connected toan electric motor that rotates in one direction to raise the filmholderand then continues to rotate for moving the film holder to a positionover a successive tank, and that rotates in the other direction to lowerthe film holder into either processing solution or rinse within thetank. T0 agitate fluid within a tank, the motor is operated a shortinterval in the direction for raising the film holder, and then it isoperated in the reverse direction to lower the film holder. r

The timing of the intervals between successive operations of the motoris provided by a tape recorder. The'control circuit for the motorincludes two switches associated with the carriage, also a thermalswitch, and

a starting relay controlled by timing signals supplied by thetaperecorder. The two switches mounted on the carriage use the supportingwires for conductors. One of these switches comprises a contact forengaging one of the wires to complete an operating circuit for themotor, and the contact engages an insulated point on the surface of thewire located over each tank to break contact with the wire for stoppingthe motor. The other switch that is located on the carrier is in areversing circuit, and it is engaged by the drive cord to hold it closedwhen the drive cord is held taut by the weight of the film holdercontaining the film that is being developed. The thermal switch isconnected in parallel with that switch on the carriage that is used tooperate and stop the motor, and it' is effective to start the motor andoperate it until it moves the carriage from over a tank and again closesthe switch thatis subsequently opened for stopping purposes.

The machine of this invention is simple to use by a hobbyist fordevelopingcolor film automatically in a lighted room. The use of wiresfor supporting the carriage and also for switching purposes, a simplecarriage, and a tape recorder for timing contribute to the low cost ofthe automatic film processor.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a front oblique view of thefilm processor of this invention; I v 3 FIG. 2 is a cross section of thefilm processor taken on the lines 2-1 of FIG. 1;

FIG. 3 is a bottom oblique view of the carriage that is shown in FIG. 1.for transporting a film holder; and

FIG. 4 is a schematic diagram of the control circuits of the motor ofthe film processor.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1, arequired number of containers or tanks 11 for processing color film ismounted in a row on the bottom of a long, narrow box 12. The container13 at the left end of the row is removable and is adapted to receive atight lid 14 so that the film to be developed can be placed in thecontainer 13 and the lid placed on the container within a photographicchanging bag to exclude light. A darkroom is not required because duringthe developing process a lid 10 is in place to cover the front side ofthe box 12.

The tanks in the row 11 contain the usual processing fluids and rinses,and each of the tanks is preferably a suitable size for holding one pintof fluid, the amount that is customarily provided in kits sold bysuppliers of photographic goods for use by hobbyists. Each of the tanks15, 16, and 17 used for rinsing by water have a lower inlet connected bya hose 18 to a water faucet, and an upper outlet connected by a hose 19to a drain.

Wires 20-22 for supporting a carriage 23 and for completing electricalswitching circuits are stretched tightly in a parallel arrangementbetween the ends of the box 12 near the top of the box over the row oftanks 11.

The carriage 23, as best shown in FIG. 3, is an E- shaped piece ofconductive metal with spaced parallel members 24-26. The carriage 23 isplaced on the center supporting wire 21 such that the end members 25 and26 are positioned above the wire and the middle 7 member 24 ispositioned below the wire. The longitudinal portion of the carriage maybe bent as required to provide a desired amount of friction between thewire 21 and the carriage 23, and thereby to provide desired control ofthe carriage as it is moved longitudinally along the wire 21. Thecarriage is held horizontally by switch contact springs 27 and 28 thatbear downwardly upon the wires 22 and 20 respectively.

A chassis 29 (FIG. 1) for a motor 30 and its electrical control circuitsare mounted at the extreme end of the boxl2 beyond the last tank in therow 11 that is used in processing a film. A motor 30 is a permanentmagnet DC motor, and it is coupled to a pulley 31 that is mounted on aspindle that functions as a reel 32. A drive cord 33 is wound on thereel and is threaded through an eye 34 that projects downwardly from thetop of the box 12 and also through an eye 35 (FIG. 2) at the bottom ofthe carriage 23, and is hooked to a ring 36 secured to the center of thetop of the lid 14. A film holder 37 is connected through a short cord 38to a ring 39 fastened to the center of the bottom of the lid 14.

With reference to FIG. 4, the application 'of power from a source ofdirect current 40 to the motor 30 is controlled by a taperecorder-reproducer 41. The output of the recorder 41 is connected to arectifier-andfilter circuit including the diode bridge 42, and the DCoutput circuit of the rectifier is connected to the base control circuitof a transistor 43. The emitter-collector circuit of the transistor 43is connected in series with the winding of a relay 44 through the courseof DC current 40. Normally, the relay 44 is released and it is operatedin response to the presence of signal on the output circuit of the taperecorder-reproducer 41 to cause the transistor 43 to become conductive.

The application of power to the motor 30 is controlled by the contactsof the relay 44. The relay has a normally open pair of contactsconnected between the heater 49 of a delay-relay 45 and the source ofcurrent 40, and two other pairs of normally open contacts connected in acircuit including the motor 30, the contacts 47 of the delay-relay 45,the carriage-supporting wires 21-22, the switching contacts 48 operatedby movement of the carriage 23, and a diode 46. A circuit for reversingthe direction of rotation of the motor 30 includes apair of normallyclosed contacts connected in the circuit including the motor 30, thecarriage-supporting wires 20 and 21, the switch 51 that is mounted onthe carriage 23 and operated by pressure applied from the cord 33, andthe diode 50. The switches 48 and 51 are described in detail in thefollowing description of operation.

To prepare the film processor for operation, the tanks 15, 16, and 17shown in FIG. 1 are supplied with clean rinse water by connecting thehose 18 to a water faucet and placing the drain hose 19 near aconvenient drain. The remaining tanks in the row of tanks 11 are filledwith film processing solutions. When the tanks are made no larger thannecessary, the amounts of solutions usually supplied in photographickits are sufficient. A source of direct-current voltage 40 is connectedto the terminals 55 and 52, and the tape record ing unit 41 is connectedto the terminals 53 and 54.

The container 13, its lid 14, and its attached film holder 37 areremoved from the box 12 to be placed in a photographic film changing bagalong with the film that is to be developed. After the film is arrangedin a loose spiral in the holder and the lid 14 is placed tightly on thecontainer 13, the container 13 is again placed in position in the row 11at the end of the box. The carriage 23 is then moved to the left alongits supporting wire 21 until it is positioned over the container 13, andthe driving cord 33 is pulled until it is slightly loose and can beattached to the ring 36 at the top of the lid 14. The lid 10 must now beplaced on the front of the box 12, and it is to remain in place at leastuntil the film has already been treated in the fixing solution.

Recording tape to provide timing has been prepared for use in therecording unit 41. The durations of audiofrequency tones that areimpressed upon the tape are dependent upon the time required for themotor 30 to move the carriage 23 between the adjacent tanks in the row11 and the time required for the film holder 37 to be raised and loweredin the same tank to provide agitation of the solution within the tank.The interval between the commencements of the tones is dependent uponthe length of time that the film is to be in the various solutions. Inone embodiment, the duration of the tones for moving the holder 37 fromone tank to the succeeding tank is 10 seconds, and the duration of thetones to cause the film holder 37 to be raised and lowered for agitationpurposes is 2 seconds.

After the tape recorder 41 is turned on, a signal having a duration ofl0 seconds is supplied by the recorder to cause the transistor 43 tobecome conductive for operating the relay 44. A circuit for operatingthe motor 30 can be traced from the terminal 52 of the power supply 40through normally open contacts of the relay 44 to a terminal of themotor 30. The circuit is continued from the other terminal of the motor30 through the carriage-supporting wire 21, the switch 48, the wire 22,the diode 46, normally open contacts of the relay 44 to the common orground circuit that is also connected to the terminal 55 of the powersupply 40. Contacts 47 of the delay-relay 45 are in parallel with thecontacts 48, but before the carriage 38 is positioned over a succeedingtank, the contacts are opened by heat supplied from the heating element49. The heating element 49 was connected to the power supply through apair of normally open contacts when the relay 44 was operated.

With reference to FIG. 3, the switch 48 comprises the spring contact 27that is in an engagement with the wire 22. A short portion of the wire22 directly over each of the tanks in the row 13 is insulated to preventelectrical contact between the spring contact 27 and the wire 22.Insulating tape or insulating material 56 that adheres to the wireprovides satisfactory insulated points. The l0-second signal supplied bythe tape recorder 41 maintains the relay 44 operated longer than thetime necessary for the carriage 23 to be moved from over the container13 to the first tank in the row 11 that contains processing solution.Also, the contact 47 of the delay-relay 45 has been opened before thecarriage 23 is positioned over the tank. Therefore, when the contact 27of the switch 48 is moved onto the insulated portion 56 of the wire 22,the operating circuit to the motor 30 is opened to stop rotation of thereel 32 and movement of the carriage 23. At the end of the ten-secondinterval when the signal being supplied by the tape recorder 41 ceases,the relay 44 releases and completes a circuit for reversing thedirection of rotation of the motor 30. The circuit can be traced fromterminal 52 of thepower supply through normally closed contacts of therelay 44, the diode 50, the carriagesupporting wire 20, the switch51,the carriage-supporting wire 21, to a terminal of the motor 30. Thecircuit is completed from the other terminal of the motor 30 throughnormally closed contacts of the relay 4.4 to the common circuit that isconnected to terminal 55 of the power supply 40. The motor 30 continuesto operate in a reverse direction to lower the film holder 37 until thecontacts 51 are opened.

As shown in FIG. 3, the switch 51 comprises spring contacts 28 and 57mounted to the carriage 23 but insulated from it by an insulator 58. Thespring contact 28 is constantly in contact with the wire 20, and is alsoconnected to that end of the spring 57 that is connected to the carriage23. Normally, a gap exists between the other end of the spring 57 andthe conductive surface of the carriage 23 and the spring 57 is movedupwardly to close the switch 51 by pressure of the operating cord 33when it is drawn taut. The cord 33 passes below the central portion ofthe spring 57, and since the spring 57 is below a straight line that canbe drawn between the eye 35 at the top of the box 12, the spring 57 ismoved upwardly with sufficient force by the weight of the loaded filmcarriage 37 to close the switch 51.

When the cord 33 slackens as the carriage 37 contacts the bottom of thetank into which it is being lowered, the switch 57 opens to stopoperation of the motor 30 until a signal is again supplied by the taperecorder 41. Since the switch 48 associated with the supporting wire 22is now opened, the circuit for starting the operation of the motor 30 tomove the carriage 23 to a position over a succeeding tank includes thecontacts 47 of the delay-relay 45. When the relay 44 was released inresponse to the cessation of signal from the tape recorder 41, thecircuit of the heating element 49 of the relay 45 was opened, andshortly thereafter the contacts 47 closed. Therefore, when the relay 44is again operated to start the motor 30 for an interval between thecircuit, the motor and the diode 46 can be traced through the contacts47 of the delay-relay 45. By the time the contacts 47 are again openedin response to current being supplied to the heating element 49 throughcontacts of the relay 44, the carriage has moved the spring 27 of theswitch 48 off the insulator 56 onto the conducting surface of the wire22. The motor then continues to operate until the next insulator 56around the wire 22 is encountered as described above.

To agitate processing fluid in a tank, signal for a short interval, suchas 2 seconds, is supplied by the tape recorder 41 after the film holder37 has been lowered into the tank. In response to the operation of therelay 44, the circuit through the contacts 47 of the delayrelay 45 asdescribed above is completed to operate the motor 30 until the filmholder 37 is raised only part of the way vertically toward the carriage23. In response to the relay 44 releasing when the short signal ceases,the circuit for reversing the operation of the motor as described aboveis completed through the switch 51 until thedriving cord 33 slackens. I

The operation of the motor 30 is repeated in response to signals beingsupplied from the tape recorder 41 until the film that is beingprocessed has been removed from the last tank in the row. After the lastcontrol signal on the tape has been supplied, the tape recorder can beshutoff either automatically or manually. The finished film can beremoved from the holder 37 at any later time.

lCLAIM: I I 1. In a film processing unithaving a row of film processingtanks, carriage means including a track supported horizontally over saidrow of tanks and a carriage mounted on said track, said carriage havingmeans for holding film, and an electric motor drivingly coupled to saidcarriage and operable to move said carriage along said track to lowersaid film successively into said tanks, to raise said film therefrom,and to transport said film therebetween, electrical control means forcontrolling operation of said motor comprising:

a timer, an operating circuit for said motor connected between saidtimer and said motor, said operating circuit including first and secondswitching means, each separately operable to be closed to complete saidoperating circuit for operating said motor,

said first switching means normally being closed for operating saidmotor, said first switching means including a switching element for eachof said tanks distributed along said track, engageable by said carriage,and operable in response to engagement by said carriage to open saidfirst switching means, each of said switching elements being positionedto be engaged by said carriage in response to said carriage being movedover a respective one of said tanks,

said timer supplying signals at different intervals dependent upon theamount of time film is to be immersed in each of said tanks, said secondswitching means being closed for a predetermined interval in response toapplication of signals from said timer to start operation of said motorfor moving said carriage, and a successive one of said switchingelements being operable in response to its engagement by said carriageto stop operation of said motor for stopping movement of said carriage Isaid track being a plurality of parallel conductive wires includingfirst and second wires, said carriage being conductive and beingslidingly mounted to said first wire, said first switching meansincluding a first switching contact means extending from said carriageto press on said second wire, and said switching elements comprisinginsulating material applied to the surface of 'said second wire at eachof the points where said first switching contact means presses on saidsecond wire when said carriage is positioned over any of said successiveones of said tanks.

2. A film processing unit as claimed in claim 1 wherein said timer is atape reproducer for reproducing recorded timing signals occurring atpredetermined intervals and having different predetermined durations.

3. A film processing unit as claimed in claim 1 wherein said secondswitching means'includes a thermal delay-relay.

4. A film processing unit as claimed in claim 1 including a reversingcircuit for said motor and wherein said track includes a third wire,said reversing circuit comprising: 1

a second switching contact means mounted on said carriage, said secondswitching contact means havextending between said reel and saidcarriage, a film holder, said carriage having an eye through which saidcord extending between said reel is loosely threaded and attached tosaid holder below said carriage, the weight of said holder maintainings-aid cord taut, said second switching contact means normally being openand being engaged by said cord in response to said cord being pulledtaut to close said second switching contact means, said second switchingmeans including normally closed reverse circuits, said normally closedreverse circuits, said third wire and said second switching contactmeans being connected in series to said motor to operate it in a reversedirection of rotation in response to release of said second switchingmeans while said second switching contact means is closed. 5. A filmprocessing unit as claimed in claim 4 wherein the first tank of said rowhas a lid to exclude light, and said lid is suspended by said cord abovesaid film holder.

1. In a film processing unit having a row of film processing tanks,carriage means including a track supported horizontally over said row oftanks and a carriage mounted on said track, said carriage having meansfor holding film, and an electric motor drivingly coupled to saidcarriage and operable to move said carriage along said track to lowersaid film successively into said tanks, to raise said film therefrom,and to transport said film therebetween, electrical control means forcontrolling operation of said motor comprising: a timer, an operatingcircuit for said motor connected between said timer and said motor, saidoperating circuit including first and second switching means, eachseparately operable to be closed to complete said operating circuit foroperatIng said motor, said first switching means normally being closedfor operating said motor, said first switching means including aswitching element for each of said tanks distributed along said track,engageable by said carriage, and operable in response to engagement bysaid carriage to open said first switching means, each of said switchingelements being positioned to be engaged by said carriage in response tosaid carriage being moved over a respective one of said tanks, saidtimer supplying signals at different intervals dependent upon the amountof time film is to be immersed in each of said tanks, said secondswitching means being closed for a predetermined interval in response toapplication of signals from said timer to start operation of said motorfor moving said carriage, and a successive one of said switchingelements being operable in response to its engagement by said carriageto stop operation of said motor for stopping movement of said carriagesaid track being a plurality of parallel conductive wires includingfirst and second wires, said carriage being conductive and beingslidingly mounted to said first wire, said first switching meansincluding a first switching contact means extending from said carriageto press on said second wire, and said switching elements comprisinginsulating material applied to the surface of said second wire at eachof the points where said first switching contact means presses on saidsecond wire when said carriage is positioned over any of said successiveones of said tanks.
 2. A film processing unit as claimed in claim 1wherein said timer is a tape reproducer for reproducing recorded timingsignals occurring at predetermined intervals and having differentpredetermined durations.
 3. A film processing unit as claimed in claim 1wherein said second switching means includes a thermal delay-relay.
 4. Afilm processing unit as claimed in claim 1 including a reversing circuitfor said motor and wherein said track includes a third wire, saidreversing circuit comprising: a second switching contact means mountedon said carriage, said second switching contact means having a portioncontacting said third wire to complete a circuit between said third wireand said carriage, a reel and a cord, said reel being operativelycoupled to said electric motor and said cord extending between said reeland said carriage, a film holder, said carriage having an eye throughwhich said cord extending between said reel is loosely threaded andattached to said holder below said carriage, the weight of said holdermaintaining s-aid cord taut, said second switching contact meansnormally being open and being engaged by said cord in response to saidcord being pulled taut to close said second switching contact means,said second switching means including normally closed reverse circuits,said normally closed reverse circuits, said third wire and said secondswitching contact means being connected in series to said motor tooperate it in a reverse direction of rotation in response to release ofsaid second switching means while said second switching contact means isclosed.
 5. A film processing unit as claimed in claim 4 wherein thefirst tank of said row has a lid to exclude light, and said lid issuspended by said cord above said film holder.